Danger Zone

• ‹ Previous program
• 65 of 1970
• Next program ›

Orion remains a highlight of the evening sky this month. The hunter is in the south at nightfall, and slides across the southwest later on. Look for his "belt" of three bright stars, with four other stars forming a large box around it.

Over the next few million years, all the stars in the belt, and all but one of the stars at the corners of the box, will blast themselves to bits as supernovae.

If any of these explosions were close enough to Earth, they could destroy our planet's ozone layer, zapping us with deadly radiation. Fortunately, though, all of Orion's future boomers are hundreds of light-years away, so they're no threat.

There's one other star, though, that could produce a far more deadly outburst. Eta Carinae, which is about 7500 light-years away, could produce a gamma-ray burst -- one of the most powerful events in the universe. Such an outburst probably accompanies the explosion of an especially heavy star -- like Eta Carinae.

A study a few years ago concluded that a gamma-ray burst anywhere in the galaxy could exterminate most of the life on Earth. The gamma rays themselves would wipe out the ozone layer, trigger a massive shock wave, and set off fires and storms. And reactions in the upper atmosphere would produce waves of deadly particles.

Luckily for us, gamma-ray bursts seem to beam into space from the poles of the exploding star. The poles of Eta Carinae don't aim our way, so we're probably safe from this doomed star.

Script by Damond Benningfield, Copyright 2008

For more skywatching tips, astronomy news, and much more, read StarDate magazine.